English

On strongly multiplicative sets

Commutative Algebra 2026-03-18 v2 Rings and Algebras

Abstract

A multiplicative subset SS of a ring RR is called \textit{strongly multiplicative} if (iΔsiR)S(\bigcap_{i\in\Delta}s_iR)\cap S \neq \emptyset for each family (si)iΔ(s_i)_{i\in\Delta} of elements in SS. In this paper, we investigate how these sets help stabilize localization and ideal operations. We show that localization and arbitrary intersections commute, meaning S1(Iα)=S1IαS^{-1}(\bigcap I_\alpha) = \bigcap S^{-1}I_\alpha for any family of ideals, if and only if SS is strongly multiplicative. Furthermore, we characterize some important classes of rings, such as total quotient rings and strongly zero-dimensional rings, in terms of strongly multiplicative sets. We also answer an open question by Hamed and Malek about whether this condition is needed for the existence of SS-minimal primes. Furthermore, we demonstrate that if SS is a strongly multiplicative set and S⊈U(R)S \not\subseteq U(R), then SS-minimal primes are not classical prime ideals, and we provide an algorithmic approach to constructing such ideals. Finally, we prove a Strong Krull's Separation Lemma, which guarantees a maximal ideal disjoint from SS. As an application of Strong Krull's Separation Lemma, we establish a one-to-one correspondence between the maximal ideals of S1RS^{-1}R and the maximal ideals of RR disjoint from a strongly multiplicative set SS of RR.

Keywords

Cite

@article{arxiv.2512.23935,
  title  = {On strongly multiplicative sets},
  author = {Suat Koç},
  journal= {arXiv preprint arXiv:2512.23935},
  year   = {2026}
}

Comments

This version includes minor revisions and improved proofs

R2 v1 2026-07-01T08:45:14.599Z